To respond to the Help? Help? Mr. Bill reply/input:
As a trained first responder, even minimally trained (below EMT),
the Good Samaritan Law has been overcome by what we are trained to say.
Specifically, "hello, my name is John Doe - Would you like me to help you???"
If they say NO. 'Bob's your uncle, All Clear, on you Go.'
In the Wilderness, Backcountry Skiing, on the Ski slopes, parking lot, car accident - in my experiences, they always say YES, Please, help !!!
Then call 9-1-1, or have lesser trained make call !!!
Then you do Scene Safe, and start your evaluation.
What you do to a non-responsive patient is your own choice.
Having an AED ( in OP's video) = the machine tells you what to do, and may administer a life saving shock.
CPR is a physically demanding exercise for even 2, once you start you are not supposed to stop til medical help arrives.

As to the purpose of the thread, i'm not original poster.
I contributed because having trained 1st responders in the general population saves many lives. More is better, even Heimlich maneuver on adults, children and babies.
Not for the faint of heart.